Rotary fluid pressure device



y 2, 1967 L. CHARLSON 3,316,814

ROTARY FLUID PRESSURE DEVICE Filed April 22, 1965 3 Sheets-Sheet 1 1NVENTOR. .L'nwv L Czmacs'ov zrraen/zr May 2, 1967 L. CHARLSON 3,316,814

ROTARY FLUID PRESSURE DEVICE Filed April 22, 1965 5 Sheets-Sheet 2 rv-INVENTOR. A Zrmv L Usmzzs'a y 2, 1967 L. CHARLSON 3,316,814

ROTARY FLUID PRESSURE DEVICE Filed April 22, 1965 3 Sheets-Sheet 5INVENTOR. Hg 6 .Zlnwv I. Czmzzsmr ATTOZ/VEV United States Patent Ofiice3,316,814 ROTARY FLUID PRESSURE DEVICE Lynn L. Charlson, Minneapolis,Minn., assignor to Germane Corporation, Minneapolis, Minn, a corporationof Minnesota Filed Apr. 22, 1965, Ser. No. 450,113 4 Claims. (Cl. 91-56)ABSTRACT OF THE DISCLOSURE The device features an orbitably moveable,ring shaped valve disposed in a valve housing for feeding and exhaustingfluid to and from expanding and contracting chambers. The orbitalmovement of the valve is synchronized with the chamber forming means andthe valve sequentially provides communication (1) between the inlet portand the expanding chambers through the center of the ring valve and (2)between the outlet port and the contracting chambers through the regionof the valve housiug which surrounds the ring shaped valve.

This invention relates generally to fluid pressure devices of the typehaving a gear reduction mechanism known in the art as a gerotor whichforms expansible and contractible chambers.

A main object of the invention is to provide a new and improved gerotortype fluid pressure device having a new and improved valving system.

Other objects and advantages will become apparent from the followingspecification, appended claims and attached drawings.

In the drawings:

FIG. 1 is a longitudinal sectional view of a fluid pressure deviceembodying the invention, and taken on line I-I of FIG. 2;

FIG. 2 is an end View from the right end of FIG. 1;

FIG. 3 is a transverse sectional view taken on line III-III of FIG. 1;

FIG. 4 is a transverse sectional view taken on line IV-IV of FIG. 1;

FIG. 5 is a transverse sectional view taken on line V-V of FIG. 1.

FIG. 6 is a separate side view of a double eccentric member which is apart of the illustrated device;

FIG. 7 is an end view from the left end of the double eccentric shown inFIG. 6; and

FIG. 8 is an end view from the right end of the double eccentric shownin FIG. 6.

In the illustrated embodiment of the invention there is provided acasing comprising a generally cylindrically and annularly shaped shaftsection 2, a cylindrically shaped gerotor section 4, a cylindrically andannularly shaped valve passage or valve plate section 5, a cylindricallyand annularly shaped end cover plate 6 and a cylindrically shaped endcover plate 8. Casing sections 2, 4, 5 and end plate are held togetherin axial alignment by a plurality of circumferentially spaced bolts 10which extend through casing sections 6, 5 and 4 and into casing section2. End plate 8 is secured to casing section 2 with a plurality ofcircumferentially arranged bolts 14.

With reference to FIGS. 1 and 3, the gerotor casing section 4, which maybe referred to as a ring member 4, has a plurality of internal teeth 16.An externally toothed star member 18, having at least one fewer teeth 20than ring member 4, is disposed eccentrically in the chamber or spaceformed and surrounded by ring member 4. Star member 18 is moveable in anorbital path about the axis 24 of ring member 4. During orbital movementof star member 18 the teeth 20 thereof intermesh with the ring memberteeth 16 to form expanding and contracting cells 25 to 30 which areequal in number to the number of teeth 20 of star member 18.

Casing section 2 has a bore 32 which is concentric relative to ring axis24 and is of small enough diameter so that the resulting annular face 34which abuts gerotor casing section 4, along with an annular face 36 ofvalve plate 5, form sides for the gerotor chamber so that the expandingand contracting cells 25 to 30 formed between the teeth of the gerotorstar and ring members 18 and 4 will be closed for all orbital positionsof the star member 18.

With further reference to FIG. 3, a vertical centerline 37 incidentallyrepresents the line of eccentricity for the star member 18 for thatparticular position of the star member relative to the ring member 4.This line of eccentricity is defined herein as a line which isperpendicular to and intersects the star and ring axes 22 and 24 for allorbital positions of the star 18. During orbital movement of the starmember 18, assuming the orbital movement is clockwise, the cells 25 to37 on the left side of the line of eccentricity would be expanding andthe cells 28 to 30 on the right side would be contracting. If theorbital movement were counterclockwise the reverse would be true. In theoperation of the device illustrated, fluid under pressure is directed tothe expanding cells on one side of the line of eccentricity andexhausted from the contracting cells on the other side of said line. Thevalving arrangement which facilitates the feeding and exhausting of thecells 25 to 30 will be described further on herein.

With reference to FIG. 1, the casing shaft section 2 has a cylindricallyshaped counterbore 38 which is concentric relative to the centerline 24which is also the centerline for ring member 4. A cylindrically shapeddrive shaft 40 having a stepped portion 42 of larger diameter isrotatably disposed in the counterbore 38 and extends through a bore 44in end plate 8. The shaft 40 may be driven by an electric motor or thelike when the device is utilized as a pump or may drive apparatus suchas a boat propeller when the device is utilized as a motor. Shaft 40 isprovided with a bore 46 which opens into and is in axial alignment withcasing bore 32, both bores being concentric relative to the devicecenterline 24.

Star member 18 has a bore 48 which is concentric relative to the axis 22thereof. The left side of the star bore 48 is optionally provided with aplurality of circumferentially arranged, axially extending teeth orsplines 50 and the left side of the shaft bore 46 also has a pluralityof circumferentially arranged, axially extending teeth or splines 52. Anintermediate shaft 54 is disposed between shaft 40 and star member 18with the left and right ends of shaft 54 having splines 56 and 58respectively which in each case are circumferentially arranged andextend axially. Splines 56 of shaft 54 are equal in number and mesh withsplines 52 of shaft 40 and the same is true at the opposite end ofintermediate shaft 54 wherein splines 58 of shaft 54 are equal in numberand mesh with splines 50 of star 18.

Star member 18 is eccentrically disposed relative to ring member 4, asmentioned above, and intermediate shaft 54 is thus always in cocked ortilted position relative to shaft 40, which has the same axis as ringmember 4, and the axis 22 of star member 18. In operation a star member18 having six teeth will make one revolution about its own axis 22 forevery six times the star member orbits in the opposite direction aboutthe axis 24 of the ring member 4. Thus, the right end of intermediateshaft 54 has both orbital and rotational movement in common with thestar member 18 while the left end of shaft 54 only has rotationalmovement in common with shaft 40. The spline connections betweenintermediate shaft 54 and shaft 40 and between intermediate shaft 54 aSi and star member 18 are forms of universal joints which permit shaft54 to have the motion described above. When the device is utilized as apump, star member 18 will be gyrated by a turning force applied to shaft40 and transmitted to star member 18 through intermediate shaft 54. Whenthe device is used as a motor, the force created by the rotation of starmember 18 about its own axis 22 will be transmitted through intermediateshaft 54 to shaft 40 to cause turning of shaft 40.

End cover plate 6 is in abutting engagement with valve plate and has abore 66 which may be concentric relative to the axis 24 of the device.Bore 60 defines a chamber which will be referred to as a valve chamber61. Valve plate 5 has a plurality of axially extending,circumferentially arranged and spaced valve passages 62 to 68 (see FIGS.1, 3 and 4) illustrated as being seven in number which is equal to thenumber of teeth of the ring member 4. Passages 62 to 68 are arranged atequal distances from axis 24 and extend from points between the ringmember teeth 16, in the chamber formed by ring member 4, to the valvechamber 61 formed by easing bore 60. The shape of each passage 62 to 68as illustrated has a cylindrical portion adjacent ring member 4 and isgenerally are shaped adjacent the valve chamber formed by the bore 60.

The wall of valve chamber 61 on the opposite side from valve plate 5 hasan annular boss portion '70 which is concentric relative to axis 24 andis in general axial alignment with valve ports 62 to 68.

Disposed in valve chamber 61 is a ring valve 72 having two main partsconcentric relative to the axis '73 of valve 72 which are an annulus 74and a hub 75. A web portion 76 connects the hub and the annulus and hasa series of circumferentially arranged openings 77. Annulus 74 hasannular surfaces 78 and 79 on opposite sides thereof which are inslidable and abutting engagement respectively with valve plate 5 andannular box 70. The inside and outside diameters of ring valve annularsurface 78 are predetermined so that annular surface 78 would be justsuflicient to cover all the valve passages 62 to 68 if ring valve 72were positioned concentrically relative to axis 24. Ring valve 72 cannotassume that position in the operation of the device, however, becausering valve 72 is disposed eccentrically in valve chamber 61 relative toaxis 24- and in operation has an orbital path about the device axis 24.

Disposed between and connecting star 18 and ring valve 72 in drivingrelation is a crank 80 having two portions 81 and 82 which areconcentric relative to the main axis of the crank and two axially spacedand angularly displaced crank portions 83 and 84 which are radiallyoffset from the main axis of the crank. The main axi of crank 80 iscoincident with the device axis 24 and the crank is rotatable relativeto the casing of the device. Crank 80 is accommodated by several boresin different parts of the device which are a bore 85 on the right sideof star 18 and concentric therewith, a bore 86 in valve plate 5concentric with the axis 24 of the device, a bore 87 in the hub 75 ofring valve 72 concentric with the axis 73 of ring valve 72, and bore 88in cover plate 6 concentric with axis 24 of the device.

Crank 80 has its two portions 81 and 82 rotatably mounted respectivelyin bores 86 and 88 of valve plate 5 and end cover 6 which are stationarymembers and these portions of the crank rotate about the axis 24. Crankportion 83 is rotatably disposed in the star bore 85 and crank portion'84 is rotatably disposed in the hub bore 87 of ring valve 72. Duringoperation of the device the orbital movement of star 18 will causerotation of crank 80 about axis 24 and the crank portion 84 will causering valve 72 to orbit in unison with star 18 Crank portion 84 isangularly displaced 90 degrees relative to crank portion 83 so thatalthough the star 18 and ring valve '72 orbit in unison, the orbiting ofthe ring valve 72 will be 90 de grees out of phase relative to theorbiting of the star 13.

Stated another way, the line of eccentricity of the ring valve 72 (seeFIG. 4) is displaced degrees relative to the line of eccentricity 37 ofthe star 18.

Casing section 6 is provided with inlet and outlet ports 92 and 93.Either of the ports 92 or 93 may be the inlet port depending on thedirection of rotation desired for the shaft 40. For convenience, port 92will be referred to herein as the inlet port 92 and port 93 will bereferred to as the outlet port 93.

Ring valve 72 divides the valve chamber 61 into two noncommunicatingchambers A and B which may be referred to as interior and exterior valvechambers and which are separated by the ring valve annulus 74. Fluidinlet port 92 is in fluid communication with interior valve chamber Aand outlet port 93 is in fluid communication with exterior valve chamberB. Interior valve chamber A includes the spaces on both sides of ringvalve web 76 in that the web openings 77 are provided to allow fluid toflow from fluid inlet port 92 to valve plate passages 62 to 68 and viceversa.

The orbital movement of ring valve 72 relative to the valve passages 62to 68 is such that at any instant, as may be noted in FIG. 4, some ofthe passages open to the inside of the ring valve to the interior valvechamber A and some of the passages communicate with the exterior valvechamber B. At that instant, for example, passages 62 to 64 are incommunication with the interior valve chamber A, valve passage 65 iscovered by annulus 7'4, and passages 66 to 68 are in communication withthe exterior valve chamber B. With reference to FIGS. 1, 3 and 4,assuming the star 18 and ring valve 72 to be in the positions shown inthose figures, fluid being admitted through inlet port 92 flows tointerior valve chamber A, through valve passages 62 to 64 to gerotorcells 25 to 27 which are expanding, from gerotor cells 28 to 30 whichare contracting through valve passages 66 to 68 to the exterior valvechamber B and out through the fluid outlet 93.

The orbiting of star 18 causes ring valve 72 to be orbited by crank 80at the same speed that star 18 orbits and in the same direction. Theorbiting of ring valve 72 sequentially exposes valve passages on theleft side of the line of eccentricity 37 to the interior valve chamber Aand simultaneously sequentially exposes valve passages on the right sideof the line of eccentricity to the exterior valve chamber B. As ringvalve 72 orbits in unison with star 18, expanding gerotor cells on theleft side of the line of eccentricity 37, which rotates about the axis24 at the same speed that the star orbits about axis 24, will always bein fluid communication with the fluid inlet port 92 and contractinggerotor cells on the right side of the line of eccentricity will alwaysbe in tfluid communication with the fluid outlet port 93. In effect thering valve 72 is indexed relative to the star 18 and, as the ring valve72 and star 18 orbit in unison, the feeding and exhausting of thegerotor cells will always be on opposite sides of the line ofeccentricity 37 for all orbital positions of the star 18 and ring valve72.

It will be understood that the invention relates generally to thevalving arrangement for feeding fluid to and exhausting fluid from thegerotor and in particular to the generally novel feature of providing avalve which performs the feeding and exhausting functions while movingin an orbital path. It is an essential characteristic of the inventionthat the orbital movement of the valve be in synchronism with theorbital movement of the star member but beyond that there are a numberof ways that the invention may be used in practice.

An obvious modification is that the ring valve can have any angulardisplacement relative to the star member if the porting in the valveplate 5 separating the star and valve chambers is arranged so that thefluid feeding and exhausting is always on opposite sides of the line ofeccentricity of the star member. If, for example, there were no angulardisplacement between the star member and the ring valve, the two ends ofeach of the ports in the valve plate could be displaced 90 degrees toachieve the same results. This would necessitate a rather complexporting arrangement for the valve plate and might be too costly to bepractical but the principle of the invention could be practiced byproviding such a porting arrangement.

If an arrangement were provided Where there would be no angulardisplacement between the star member and the ring valve, the crankmember could be eliminated and the ring valve could be actuated by theintermediate shaft if the intermediate shaft were extended and connectedto the ring valve. The extended portion of the intermediate shaft wouldmove in an orbital path and if a universal joint type of slidingconnection were provided between the extended shaft portion and the ringvalve the ring valve would orbit in phase and in synchronism with theorbital movement of the star member.

Another obvious modification would be to eliminate or not provide thevalve plate 5 between the star and valve chambers. The ring valve wouldbe in direct abutting and sliding engagement with the gerotor ring andstar members. In that construction, however, the ring valve would haveto be angularly displaced 90 degrees relative to the star member asshown in the illustrated embodiment of the invention.

Another possible modification is that a drive shaft could be providedthat rotates in synchronism with the orbital movement of the starmember, as is known in the art, instead of a drive shaft that rotates insynchronism with the rotating movement of the star member as shown inthe illustrated embodiment of the invention and which is also known inthe art. If either type of drive shaft is provided the device will besuitable to function as a pump or a motor but a third alternative existswhich is to provide no drive shaft at all in that case wherein thedevice may be used as a metering device which is also known in the art.

While one embodiment of the invention is described here, it will beunderstood that it is capable of modification, and that suchmodification, including a reversal of parts, may be made withoutdeparture from the spirit and scope of the invention as defined in theclaims.

What I claim is:

1. In a fluid pressure device, fluid inlet and outlet means, casingmeans including an internally toothed ring member defining the outerwall of a chamber, a cooperating externally toothed star member havingfewer teeth than said ring member disposed eccentrically in saidchamber, one of said members having orbital movement about the axis ofthe other of said members and one of said members having rotationalmovement about its own axis in the opposite direction from and at aslower speed than said orbital movement during relative movement betweensaid members, the teeth of said members intermeshing to form expandingcells on one side of the line of eccentricity and contracting cells onthe other side of said line during relative movement between saidmembers, valve means including a valve element, said valve means havingfluid supply passage means for admitting fluid from said fluid inletmeans to said expanding cells and fluid exhaust passage means forexhausting fluid from said contracting cells, and valve drive means forimparting orbital movement to said valve element in synchronism withsaid orbital movement of the orbiting one of said star member, whereinsaid valve means includes a valve chamber formed by said casing and saidvalve element is disposed eccentrically in said valve chamber, saidvalve element being ring shaped with one of said passage means beinginternally thereof and the other of said passage means being externallythereof.

2. In a fluid pressure device, fluid inlet and outlet means, casingmeans including an internally toothed ring member defining the outerwall of a chamber, a cooperating externally toothed star member havingfewer teeth than said ring member disposed eccentrically in saidchamber, one of said members having orbital movement about the axis ofthe other of said members and one of said members having rotationalmovement about its own axis in the opposite direction from and at aslower speed than said orbital movement during relative movement betweensaid members, the teeth of said members intermeshing to form expandingcells on one side of the line of eccentricity and contracting cells onthe other side of said line during relative movement between saidmembers, valve means including a valve element, said valve means havingfluid supply passage means for admitting fluid from said fluid inletmeans to said expanding cells and fluid exhaust passage means forexhausting fluid from said contracting cells, and valve drive means forimparting orbital movement to said valve element in synchronism withsaid orbital movement of the orbiting one of said star member, whereinsaid star member and said valve element each has a centrally locatedbore, said valve drive means being a crank member which is rotatably andcoaxially disposed relative to said ring member, said crank memberhaving two eccentrically disposed crank portions angularly displaceddegrees from each other, one of said crank portions being slidablydisposed in said star member bore and the other of said crank portionsbeing slidably disposed in said valve element bore.

3. A fluid pressure device according to claim 1 wherein a valve plate isdisposed between said star and valve chambers, said valve plate having aseries of ports arranged circumferentially relative to the axis of saidring member and extending through said valve plate to providecommunication between said star and valve chambers, said ports beingequal in number to the teeth of said ring member, said ports beingspaced from the ring member axis a distance equal to about one-half theinside diameter of said valve element.

4. A fluid pressure device according to claim 3 wherein the shapes ofsaid ports in the surface of said valve plate adjacent said valvechamber are are shaped.

References Cited by the Examiner UNITED STATES PATENTS 3,233,524 2/1966Charlson 91--56 3,261,235 7/1966 Henkel 91-56 X 3,270,681 9/1966Charlson 1 0 3-430 MARTIN P. SCHWADRON, Primary Examiner. G. N. BAUM,Assistant Examiner.

1. IN A FLUID PRESSURE DEVICE, FLUID INLET AND OUTLET MEANS, CASINGMEANS INCLUDING AN INTERNALLY TOOTHED RING MEMBER DEFINING THE OUTERWALL OF A CHAMBER, A COOPERATING EXTERNALLY TOOTHED STAR MEMBER HAVINGFEWER TEETH THAN SAID RING MEMBER DISPOSED ECCENTRICALLY IN SAIDCHAMBER, ONE OF SAID MEMBERS HAVING ORBITAL MOVEMENT ABOUT THE AXIS OFTHE OTHER OF SAID MEMBERS AND ONE OF SAID MEMBERS HAVING ROTATIONALMOVEMENT ABOUT ITS OWN AXIS IN THE OPPOSITE DIRECTION FROM AND AT ASLOWER SPEED THAN SAID ORBITAL MOVEMENT DURING RELATIVE MOVEMENT BETWEENSAID MEMBERS, THE TEETH OF SAID MEMBERS INTERMESHING TO FORM EXPANDINGCELLS ON ONE SIDE OF THE LINE OF ECCENTRICITY AND CONTRACTING CELLS ONTHE OTHER SIDE OF SAID LINE DURING RELATIVE MOVEMENT BETWEEN SAIDMEMBERS, VALVE MEANS INCLUDING A VALVE ELEMENT, SAID VALVE MEANS HAVINGFLUID SUPPLY PASSAGE MEANS FOR ADMITTING FLUID FROM SAID FLUID INLETMEANS TO SAID EXPANDING CELLS AND FLUID EXHAUST PASSAGE MEANS FOREXHAUSTING FLUID FROM SAID CONTRACTING CELLS, AND VALVE DRIVE MEANS FORIMPARTING ORBITAL MOVEMENT TO SAID VALVE ELEMENT IN SYNCHRONISM WITHSAID ORBITAL MOVEMENT OF THE ORBITING ONE OF SAID STAR MEMBER, WHEREINSAID VALVE MEANS INCLUDES A VALVE CHAMBER FORMED BY SAID CASING AND SAIDVALVE ELEMENT IS DISPOSED ECCENTRICALLY IN SAID VALVE CHAMBER, SAIDVALVE ELEMENT BEING RING SHAPED WITH ONE OF SAID PASSAGE MEANS BEINGINTERNALLY THEREOF AND THE OTHER OF SAID PASSAGE MEANS BEING EXTERNALLYTHEREOF.